1. Field of the Invention
The present invention relates to a transistor device and, more particularly, to a structure of a transistor assembly which is suitable to fabricate a high-frequency and high-power transistor device.
2. Description of the Prior Art
In the prior art, a high-frequency and high-power transistor device is constructed so as to form a so-called strip line type structure, due to which strip line type structure it is easy to form a large size conductor and to reduce an inductive reactance component so as to satisfy the requirement of the high-frequency and high-power characteristics of a transistor device. In the strip line type transistor device of the prior art, as will be mentioned in detail hereinafter, an emitter bridge is one of the important members thereof. The emitter bridge is very useful for electrically connecting a transistor chip element and both of two separate emitter leads, by way of so-called bonding wires having a very short length. The above mentioned emitter bridge is usually made of an Au-Si alloy and is fixedly bridged between the two separate emitter leads. However, the strip line type transistor device creates a defect. The defect is that it requires very high skill to fabricate the emitter bridge to be connected between the two separate emitter leads, and therefore, firstly the transistor device becomes very high in cost and, secondly it is difficult to make the transistor devices under a mass production method. Further, since the height of the emitter bridge from an emitter area of the transistor chip element is relatively high, an undesirable difference in level between the emitter bridge and the emitter area is created. Accordingly, it is not easy to achieve the so-called wire bonding operation. This fact also causes the mass production of the transistor device to be very difficult.